I recently ran Waterdeep Dragon Heist set on Ravnica - it went rather well, if I do say so myself. I basically said in my own head that the War of the Spark was not going to happen, and that all the inter-guild tension described in the book was over the missing treasure horde in Dragon Heist. I did tone the Rakdos down a bit since I had a player who wanted to play one without being disruptive. The players made characters all from different guilds - which I encouraged, since GGtR says it can support multi-guild parties! It worked fine. Broke down the faction missions and whatnot and reassigned them individually to appropriate guilds rather than trying to match the Dragon Heist factions 1-to-1 to guilds. The biggest problem I ran into, I think, was properly communicating how bizarrely exaggerated the architecture of Ravnica could get. The map in GGtR really doesn't match the art on the cards in the sets when it comes to the scale of buildings - which is unfortunate, because I remember "there's a map of the Tenth District" being a pretty big selling point in the marketing.
